The eight robberies spanned the metropolitan area including Christies Beach, Bowden, Fairview Park, Elizabeth East and Mount Barker.The alleged victims selling jewellery, mobile phones and other personal items were targeted primarily through Facebook Marketplace.Police allege when the victims met with a potential buyer they were assaulted and robbed. On Thursday John Garang, 25, of Salisbury East, appeared in court charged with two counts of aggravated robbery and one count of illegal use.He did not apply for bail and will appear in the Adelaide Magistrates Court in April next year. Emmanuel Sumo, 25, also appeared in court and did not apply for bail.He is charged with charged with six counts of aggravated robbery, illegal use, two counts of theft, attempted theft and deception. He will appear in court on those offences in April.Both of the men were arrested on Wednesday following a traffic stop at Blair Athol.Police allege a search of the vehicle revealed further suspected stolen property. Officers also seized a knife and knuckleduster. The previous day a search of a property linked to one of the suspects allegedly revealed two stolen motorbikes and a gel blaster.Though Gumtree and Facebook Marketplace are popular platforms for people to privately sell items, police have urged people to consider their personal safety when meeting people online. Police said when meeting someone, always try to meet in a public setting, ideally with CCTV cameras and during the day. They also advised sellers to tell someone where they are going and attempt to find out information such as the buyer’s name, phone number or address.